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1.
J Appl Clin Med Phys ; 22(6): 26-34, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34036736

RESUMO

PURPOSE: Linear accelerator quality assurance (QA) in radiation therapy is a time consuming but fundamental part of ensuring the performance characteristics of radiation delivering machines. The goal of this work is to develop an automated and standardized QA plan generation and analysis system in the Oncology Information System (OIS) to streamline the QA process. METHODS: Automating the QA process includes two software components: the AutoQA Builder to generate daily, monthly, quarterly, and miscellaneous periodic linear accelerator QA plans within the Treatment Planning System (TPS) and the AutoQA Analysis to analyze images collected on the Electronic Portal Imaging Device (EPID) allowing for a rapid analysis of the acquired QA images. To verify the results of the automated QA analysis, results were compared to the current standard for QA assessment for the jaw junction, light-radiation coincidence, picket fence, and volumetric modulated arc therapy (VMAT) QA plans across three linacs and over a 6-month period. RESULTS: The AutoQA Builder application has been utilized clinically 322 times to create QA patients, construct phantom images, and deploy common periodic QA tests across multiple institutions, linear accelerators, and physicists. Comparing the AutoQA Analysis results with our current institutional QA standard the mean difference of the ratio of intensity values within the field-matched junction and ball-bearing position detection was 0.012 ± 0.053 (P = 0.159) and is 0.011 ± 0.224 mm (P = 0.355), respectively. Analysis of VMAT QA plans resulted in a maximum percentage difference of 0.3%. CONCLUSION: The automated creation and analysis of quality assurance plans using multiple APIs can be of immediate benefit to linear accelerator quality assurance efficiency and standardization. QA plan creation can be done without following tedious procedures through API assistance, and analysis can be performed inside of the clinical OIS in an automated fashion.


Assuntos
Aceleradores de Partículas , Radioterapia de Intensidade Modulada , Automação , Humanos , Imagens de Fantasmas , Garantia da Qualidade dos Cuidados de Saúde , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Software
2.
J Virol ; 92(9)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29444939

RESUMO

Viral infection and replication are affected by host cell heterogeneity, but the mechanisms underlying the effects remain unclear. Using single-cell analysis, we investigated the effects of host cell heterogeneity, including cell size, inclusion, and cell cycle, on foot-and-mouth disease virus (FMDV) infection (acute and persistent infections) and replication. We detected various viral genome replication levels in FMDV-infected cells. Large cells and cells with a high number of inclusions generated more viral RNA copies and viral protein and a higher proportion of infectious cells than other cells. Additionally, we found that the viral titer was 10- to 100-fold higher in cells in G2/M than those in other cell cycle phases and identified a strong correlation between cell size, inclusion, and cell cycle heterogeneity, which all affected the infection and replication of FMDV. Furthermore, we demonstrated that host cell heterogeneity influenced the adsorption of FMDV due to differences in the levels of FMDV integrin receptors expression. Collectively, these results further our understanding of the evolution of a virus in a single host cell.IMPORTANCE It is important to understand how host cell heterogeneity affects viral infection and replication. Using single-cell analysis, we found that viral genome replication levels exhibited dramatic variability in foot-and-mouth disease virus (FMDV)-infected cells. We also found a strong correlation between heterogeneity in cell size, inclusion number, and cell cycle status and that all of these characteristics affect the infection and replication of FMDV. Moreover, we found that host cell heterogeneity influenced the viral adsorption as differences in the levels of FMDV integrin receptors' expression. This study provided new ideas for the studies of correlation between FMDV infection mechanisms and host cells.


Assuntos
Tamanho Celular , Vírus da Febre Aftosa/fisiologia , Pontos de Checagem da Fase M do Ciclo Celular/fisiologia , Análise de Célula Única/métodos , Replicação Viral/fisiologia , Animais , Linhagem Celular , Cricetinae , Febre Aftosa/virologia , Vírus da Febre Aftosa/genética , Genoma Viral/genética , RNA Viral/genética , Carga Viral/fisiologia
3.
Virol Sin ; 35(1): 52-63, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31512107

RESUMO

Foot-and-mouth disease virus (FMDV) rapidly causes cytopathic effects in susceptible cells. Incomplete viral clearance during the acute infection leads to persistent infection. The relationship between host gene expression and the persistent infection remains unclear. In this study, we analyzed the transcriptome profiles of BHK-21 cells acutely and persistently infected with FMDV to identify differences in gene expression. GO and KEGG enrichment analyses showed that the 8,378 differentially expressed genes were significantly enriched in categories including metabolism, biosynthesis, ribosome function, and endocytosis. In persistently infected BHK-21 cells, ribosome- and translation-related genes were significantly down-regulated. There were more differentially expressed immune-related genes during persistent infection than during acute infection. Two hundred and seventy-four genes were differentially expressed in both acutely and persistently infected BHK-21 cells. Among these genes, heat shock protein family B member 1 (Hspb1) knockdown significantly inhibited FMDV replication. Our research provides a basis for further research to understand the mechanisms of persistent FMDV infection including the genes involved in FMDV replication.


Assuntos
Vírus da Febre Aftosa/genética , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Replicação Viral/genética , Doença Aguda , Animais , Linhagem Celular , Cricetinae , Febre Aftosa/virologia , Vírus da Febre Aftosa/fisiologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Imunidade Celular , Rim/citologia , Rim/virologia , RNA Viral/genética
4.
Sci Rep ; 8(1): 5074, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29568077

RESUMO

Food-and-mouth disease virus (FMDV) is a highly contagious virus that seriously threatens the development of animal husbandry. Although persistent FMDV infection can dramatically worsen the situation, the mechanisms involved in persistent FMDV infection remain unclear. In the present study, we identified the presence of evolved cells in the persistently FMDV-infected cell line. These cells exhibited resistance to the parent FMDV and re-established persistent infection when infected with FMDV-Op (virus supernatant of persistent infection cell lines), emphasizing the decisive role of evolved host cells in the establishment of persistent FMDV infection. Using RNA-seq, we identified the gene expression profiles of these evolved host cells. In total, 4,686 genes were differentially expressed in evolved cells compared with normal cells, with these genes being involved in metabolic processes, cell cycle, and cellular protein catabolic processes. In addition, 1,229 alternative splicing events, especially skipped exon events, were induced in evolved cells. Moreover, evolved cells exhibited a stronger immune defensive response and weaker MAPK signal response than normal cells. This comprehensive transcriptome analysis of evolved host cells lays the foundation for further investigations of the molecular mechanisms of persistent FMDV infection and screening for genes resistant to FMDV infection.


Assuntos
Vírus da Febre Aftosa/genética , Febre Aftosa/genética , Interações Hospedeiro-Patógeno/genética , Transcriptoma/genética , Processamento Alternativo/genética , Animais , Bovinos , Doenças dos Bovinos/genética , Doenças dos Bovinos/virologia , Linhagem Celular/virologia , Febre Aftosa/virologia , Vírus da Febre Aftosa/patogenicidade , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Mesocricetus/genética , Camundongos , Replicação Viral/genética
5.
Phys Med Biol ; 61(24): N697-N707, 2016 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-27910826

RESUMO

Studies show that radiotherapy of a primary tumor in combination with immunoadjuvants (IA) can result in increased survival or immune-mediated regression of metastasis outside the radiation field, a phenomenon known as abscopal effect. However, toxicities due to repeated systematic administration of IA have been shown to be a major obstacle in clinical trials. To minimize the toxicities and prime a more potent immune response, Ngwa et al have proposed that inert radiotherapy biomaterials such as fiducials could be upgraded to multifunctional ones loaded with IA for in situ delivery directly into the tumor sub-volume at no additional inconvenience to patients. In this preliminary study, the potential of such an approach is investigated for lung cancer using anti-CD40 antibody. First the benefit of using the anti-CD40 delivered in situ to enhance radiotherapy was tested in mice with subcutaneous tumors generated with the Lewis Lung cancer cell line LL/2 (LLC-1). The tumors were implanted on both flanks of the mice to simulate metastasis. Tumors on one flank were treated with and without anti-CD40 and the survival benefits compared. An experimentally determined in vivo diffusion coefficient for nanoparticles was then employed to estimate the time for achieving intratumoral distribution of the needed minimal concentrations of anti-CD40 nanoparticles if released from a multifuntional radiotherapy biomaterials. The studies show that the use of anti-CD40 significantly enhanced radiotherapy effect, slowing the growth of the treated and untreated tumors, and increasing survival. Meanwhile our calculations indicate that for a 2-4 cm tumor and 7 mg g-1 IA concentrations, it would take 4.4-17.4 d, respectively, following burst release, for the required concentration of IA nanoparticles to accumulate throughout the tumor during image-guided radiotherapy. The distribution of IA could be customized as a function of loading concentrations or nanoparticle size to fit current Stereotactic Body Radiotherapy schedules. Overall, the preliminary results support ongoing work in developing multifunctional radiotherapy biomaterials for in situ delivery of immunoadjuvants such as anti-CD40 to leverage the abscopal effect, while minimizing systemic toxicities. The potential of extending such an approach to other cancer types is discussed.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Materiais Biocompatíveis/química , Carcinoma Pulmonar de Lewis/radioterapia , Nanopartículas/administração & dosagem , Radiossensibilizantes/administração & dosagem , Animais , Materiais Biocompatíveis/administração & dosagem , Braquiterapia , Antígenos CD40/imunologia , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Carga Tumoral
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